1. Field
Example embodiments relate to semiconductor devices, and more particularly, to nonvolatile memory devices capable of storing data and methods of operating the same.
2. Description of the Conventional Art
Nonvolatile memory devices, e.g., electronically erasable programmable read only memories (EEPROMs) or flash memories may store data even when power is turned off, and further, stored data may be erased there from and new data may be programmed thereto. Nonvolatile memory devices may be used in semiconductor products, e.g., storage media for mobile devices or portable memory sticks, etc.
Recently, with the trend toward smaller semiconductor products, nonvolatile memory devices used in the semiconductor products have become highly integrated. For example, three-dimensional nonvolatile memory devices may have a higher degree of integration in a plane compared to planar-type nonvolatile memory devices and may be manufactured using silicon-on-insulator (SOI) substrates or nanowire structures. However, in three-dimensional nonvolatile memory devices, a semiconductor layer used as a channel is insulated from a substrate. Thus, like in conventional planar-type nonvolatile memory devices, it is difficult to perform an erasing operation when using a substrate. However, an erasing voltage may be directly applied to a semiconductor layer, but, a high voltage circuit may be additionally required and/or an operating speed may be reduced.